Computers include various components, such as a central processing unit (CPU), memory, mass storage, and so forth. As software applications executable in such computers have become ever more powerful, the demands placed by such software applications on computing resources, such as memory capacity, of a computer have also increased. Typically, a memory subsystem within a computer is made up of memory modules inserted into one or more memory sockets or slots that are arranged either on the motherboard or a peripheral board in the computer. Empty memory slots are typically available to enable a user to add memory modules to the memory subsystem.
In many computers, adding memory modules to a computer typically involves first shutting down the computer before the memory modules are added. For most desktop or portable applications, shutting down the computer to add memory capacity is usually acceptable. However, most network applications rely upon a network server being available a high percentage of the time. Shutting down a server, or some other type of computer where high availability is useful, to perform memory capacity upgrades may not be desirable.
To address this, hot plugging techniques have been implemented to enable new memory modules to be inserted into available (empty) memory slots in a computer while the system remains live (that is, while the system is operating and remains available).
When adding new memory modules, there is a possibility that the new memory modules may be defective. Conventionally, when a computer detects a defective memory module that cannot be corrected using error detection and correction logic, a system error is indicated that may cause the system to shut down. In such computers, a defect in a newly added memory module may also result in shutdown of the computer, which makes the computer unavailable.